MeshTopoUtil.cpp

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/**
 * MOAB, a Mesh-Oriented datABase, is a software component for creating,
 * storing and accessing finite element mesh data.
 *
 * Copyright 2004 Sandia Corporation. Under the terms of Contract
 * DE-AC04-94AL85000 with Sandia Corporation, the U.S. Government
 * retains certain rights in this software.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 */
 
#ifdef WIN32
#pragma warning( disable : 4786 )
#endif
 
#include "moab/MeshTopoUtil.hpp"
#include "moab/Range.hpp"
#include "Internals.hpp"
#include "moab/Interface.hpp"
#include "moab/CN.hpp"
 
#include <cassert>
 
#define RR \
 { \
 if( MB_SUCCESS != result ) return result; \
 }
 
namespace moab
{
 
//! generate all the AEntities bounding the vertices
ErrorCode MeshTopoUtil::construct_aentities( const Range& vertices )
{
 Range out_range;
 ErrorCode result;
 result = mbImpl->get_adjacencies( vertices, 1, true, out_range, Interface::UNION );
 if( MB_SUCCESS != result ) return result;
 out_range.clear();
 result = mbImpl->get_adjacencies( vertices, 2, true, out_range, Interface::UNION );
 if( MB_SUCCESS != result ) return result;
 out_range.clear();
 result = mbImpl->get_adjacencies( vertices, 3, true, out_range, Interface::UNION );
 
 return result;
}
 
//! given an entity, get its average position (avg vertex locations)
ErrorCode MeshTopoUtil::get_average_position( Range& entities, double* avg_position )
{
 std::vector< EntityHandle > ent_vec;
 std::copy( entities.begin(), entities.end(), std::back_inserter( ent_vec ) );
 return get_average_position( &ent_vec[0], ent_vec.size(), avg_position );
}
 
//! given an entity, get its average position (avg vertex locations)
ErrorCode MeshTopoUtil::get_average_position( const EntityHandle* entities,
 const int num_entities,
 double* avg_position )
{
 double dum_pos[3];
 avg_position[0] = avg_position[1] = avg_position[2] = 0.0;
 
 Range connect;
 ErrorCode result = mbImpl->get_adjacencies( entities, num_entities, 0, false, connect, Interface::UNION );
 if( MB_SUCCESS != result ) return result;
 
 if( connect.empty() ) return MB_FAILURE;
 
 for( Range::iterator rit = connect.begin(); rit != connect.end(); ++rit )
 {
 result = mbImpl->get_coords( &( *rit ), 1, dum_pos );
 if( MB_SUCCESS != result ) return result;
 avg_position[0] += dum_pos[0];
 avg_position[1] += dum_pos[1];
 avg_position[2] += dum_pos[2];
 }
 avg_position[0] /= (double)connect.size();
 avg_position[1] /= (double)connect.size();
 avg_position[2] /= (double)connect.size();
 
 return MB_SUCCESS;
}
 
//! given an entity, get its average position (avg vertex locations)
ErrorCode MeshTopoUtil::get_average_position( const EntityHandle entity, double* avg_position )
{
 const EntityHandle* connect = NULL;
 int num_connect = 0;
 if( MBVERTEX == mbImpl->type_from_handle( entity ) ) return mbImpl->get_coords( &entity, 1, avg_position );
 
 ErrorCode result = mbImpl->get_connectivity( entity, connect, num_connect );
 if( MB_SUCCESS != result ) return result;
 
 return get_average_position( connect, num_connect, avg_position );
}
 
// given an entity, find the entities of next higher dimension around
// that entity, ordered by connection through next higher dimension entities;
// if any of the star entities is in only one entity of next higher dimension,
// on_boundary is returned true
ErrorCode MeshTopoUtil::star_entities( const EntityHandle star_center,
 std::vector< EntityHandle >& star_ents,
 bool& bdy_entity,
 const EntityHandle starting_star_entity,
 std::vector< EntityHandle >* star_entities_dp2,
 Range* star_candidates_dp2 )
{
 // now start the traversal
 bdy_entity = false;
 EntityHandle last_entity = starting_star_entity, last_dp2 = 0, next_entity, next_dp2;
 std::vector< EntityHandle > star_dp2;
 ErrorCode result;
 int center_dim = mbImpl->dimension_from_handle( star_center );
 
 Range tmp_candidates_dp2;
 if( NULL != star_candidates_dp2 )
 tmp_candidates_dp2 = *star_candidates_dp2;
 else
 {
 result = mbImpl->get_adjacencies( &star_center, 1, center_dim + 2, false, tmp_candidates_dp2 );
 if( MB_SUCCESS != result ) return result;
 }
 
 do
 {
 // get the next star entity
 result = star_next_entity( star_center, last_entity, last_dp2, &tmp_candidates_dp2, next_entity, next_dp2 );
 if( MB_SUCCESS != result ) return result;
 
 // special case: if starting_star_entity isn't connected to any entities of next
 // higher dimension, it's the only entity in the star; put it on the list and return
 if( star_ents.empty() && next_entity == 0 && next_dp2 == 0 )
 {
 star_ents.push_back( last_entity );
 bdy_entity = true;
 return MB_SUCCESS;
 }
 
 // if we're at a bdy and bdy_entity hasn't been set yet, we're at the
 // first bdy; reverse the lists and start traversing in the other direction; but,
 // pop the last star entity off the list and find it again, so that we properly
 // check for next_dp2
 if( 0 == next_dp2 && !bdy_entity )
 {
 star_ents.push_back( next_entity );
 bdy_entity = true;
 std::reverse( star_ents.begin(), star_ents.end() );
 star_ents.pop_back();
 last_entity = star_ents.back();
 if( !star_dp2.empty() )
 {
 std::reverse( star_dp2.begin(), star_dp2.end() );
 last_dp2 = star_dp2.back();
 }
 }
 // else if we're not on the bdy and next_entity is already in star, that means
 // we've come all the way around; don't put next_entity on list again, and
 // zero out last_dp2 to terminate while loop
 else if( !bdy_entity && std::find( star_ents.begin(), star_ents.end(), next_entity ) != star_ents.end() &&
 ( std::find( star_dp2.begin(), star_dp2.end(), next_dp2 ) != star_dp2.end() || !next_dp2 ) )
 {
 last_dp2 = 0;
 }
 
 // else, just assign last entities seen and go on to next iteration
 else
 {
 if( std::find( star_ents.begin(), star_ents.end(), next_entity ) == star_ents.end() )
 star_ents.push_back( next_entity );
 if( 0 != next_dp2 )
 {
 star_dp2.push_back( next_dp2 );
 tmp_candidates_dp2.erase( next_dp2 );
 }
 last_entity = next_entity;
 last_dp2 = next_dp2;
 }
 } while( 0 != last_dp2 );
 
 // copy over the star_dp2 list, if requested
 if( NULL != star_entities_dp2 ) ( *star_entities_dp2 ).swap( star_dp2 );
 
 return MB_SUCCESS;
}
 
ErrorCode MeshTopoUtil::star_next_entity( const EntityHandle star_center,
 const EntityHandle last_entity,
 const EntityHandle last_dp1,
 Range* star_candidates_dp1,
 EntityHandle& next_entity,
 EntityHandle& next_dp1 )
{
 // given a star_center, a last_entity (whose dimension should be 1 greater than center)
 // and last_dp1 (dimension 2 higher than center), returns the next star entity across
 // last_dp1, and the next dp1 entity sharing next_entity; if star_candidates is non-empty,
 // star must come from those
 Range from_ents, to_ents;
 from_ents.insert( star_center );
 if( 0 != last_dp1 ) from_ents.insert( last_dp1 );
 
 int dim = mbImpl->dimension_from_handle( star_center );
 
 ErrorCode result = mbImpl->get_adjacencies( from_ents, dim + 1, true, to_ents );
 if( MB_SUCCESS != result ) return result;
 
 // remove last_entity from result, and should only have 1 left, if any
 if( 0 != last_entity ) to_ents.erase( last_entity );
 
 // if no last_dp1, contents of to_ents should share dp1-dimensional entity with last_entity
 if( 0 != last_entity && 0 == last_dp1 )
 {
 Range tmp_to_ents;
 for( Range::iterator rit = to_ents.begin(); rit != to_ents.end(); ++rit )
 {
 if( 0 != common_entity( last_entity, *rit, dim + 2 ) ) tmp_to_ents.insert( *rit );
 }
 to_ents = tmp_to_ents;
 }
 
 if( 0 == last_dp1 && to_ents.size() > 1 && NULL != star_candidates_dp1 && !star_candidates_dp1->empty() )
 {
 // if we have a choice of to_ents and no previous dp1 and there are dp1 candidates,
 // the one we choose needs to be adjacent to one of the candidates
 result = mbImpl->get_adjacencies( *star_candidates_dp1, dim + 1, true, from_ents, Interface::UNION );
 if( MB_SUCCESS != result ) return result;
 to_ents = intersect( to_ents, from_ents );
 }
 
 if( !to_ents.empty() )
 next_entity = *to_ents.begin();
 else
 {
 next_entity = 0;
 next_dp1 = 0;
 return MB_SUCCESS;
 }
 
 // get next_dp1
 if( 0 != star_candidates_dp1 )
 to_ents = *star_candidates_dp1;
 else
 to_ents.clear();
 
 result = mbImpl->get_adjacencies( &next_entity, 1, dim + 2, true, to_ents );
 if( MB_SUCCESS != result ) return result;
 
 // can't be last one
 if( 0 != last_dp1 ) to_ents.erase( last_dp1 );
 
 if( !to_ents.empty() ) next_dp1 = *to_ents.begin();
 
 // could be zero, means we're at bdy
 else
 next_dp1 = 0;
 
 return MB_SUCCESS;
}
 
ErrorCode MeshTopoUtil::star_entities_nonmanifold( const EntityHandle star_entity,
 std::vector< std::vector< EntityHandle > >& stars,
 std::vector< bool >* bdy_flags,
 std::vector< std::vector< EntityHandle > >* dp2_stars )
{
 // Get a series of (d+1)-dimensional stars around a d-dimensional entity, such that
 // each star is on a (d+2)-manifold containing the d-dimensional entity; each star
 // is either open or closed, and also defines a (d+2)-star whose entities are bounded by
 // (d+1)-entities on the star and on the (d+2)-manifold
 //
 // Algorithm:
 // get the (d+2)-manifold entities; for d=1 / d+2=3, just assume all connected elements, since
 // we don't do 4d yet
 // get intersection of (d+1)-entities adjacent to star entity and union of (d+1)-entities
 // adjacent to (d+2)-manifold entities; these will be the entities in the star
 // while (d+1)-entities
 // remove (d+1)-entity from (d+1)-entities
 // get the (d+1)-star and (d+2)-star around that (d+1)-entity (using star_entities)
 // save that star to the star list, and the bdy flag and (d+2)-star if requested
 // remove (d+2)-entities from the (d+2)-manifold entities
 // remove (d+1)-entities from the (d+1)-entities
 // (end while)
 
 int this_dim = mbImpl->dimension_from_handle( star_entity );
 if( 3 <= this_dim || 0 > this_dim ) return MB_FAILURE;
 
 // get the (d+2)-manifold entities; for d=1 / d+2=3, just assume all connected elements, since
 // we don't do 4d yet
 Range dp2_manifold;
 ErrorCode result = get_manifold( star_entity, this_dim + 2, dp2_manifold );
 if( MB_SUCCESS != result ) return result;
 
 // get intersection of (d+1)-entities adjacent to star and union of (d+1)-entities
 // adjacent to (d+2)-manifold entities; also add manifold (d+1)-entities, to catch
 // any not connected to (d+2)-entities
 Range dp1_manifold;
 result = mbImpl->get_adjacencies( dp2_manifold, this_dim + 1, false, dp1_manifold, Interface::UNION );
 if( MB_SUCCESS != result ) return result;
 
 result = mbImpl->get_adjacencies( &star_entity, 1, this_dim + 1, false, dp1_manifold );
 if( MB_SUCCESS != result ) return result;
 
 result = get_manifold( star_entity, this_dim + 1, dp1_manifold );
 if( MB_SUCCESS != result ) return result;
 
 // while (d+1)-entities
 while( !dp1_manifold.empty() )
 {
 
 // get (d+1)-entity from (d+1)-entities (don't remove it until after star,
 // since the star entities must come from dp1_manifold)
 EntityHandle this_ent = *dp1_manifold.begin();
 
 // get the (d+1)-star and (d+2)-star around that (d+1)-entity (using star_entities)
 std::vector< EntityHandle > this_star_dp1, this_star_dp2;
 bool on_bdy;
 result = star_entities( star_entity, this_star_dp1, on_bdy, this_ent, &this_star_dp2, &dp2_manifold );
 if( MB_SUCCESS != result ) return result;
 
 // if there's no star entities, it must mean this_ent isn't bounded by any dp2
 // entities (wasn't put into star in star_entities 'cuz we're passing in non-null
 // dp2_manifold above); put it in
 if( this_star_dp1.empty() )
 {
 Range dum_range;
 result = mbImpl->get_adjacencies( &this_ent, 1, this_dim + 2, false, dum_range );
 if( MB_SUCCESS != result ) return result;
 if( dum_range.empty() ) this_star_dp1.push_back( this_ent );
 }
 
 // now we can remove it
 dp1_manifold.erase( dp1_manifold.begin() );
 
 // save that star to the star list, and the bdy flag and (d+2)-star if requested
 if( !this_star_dp1.empty() )
 {
 stars.push_back( this_star_dp1 );
 if( NULL != bdy_flags ) bdy_flags->push_back( on_bdy );
 if( NULL != dp2_stars ) dp2_stars->push_back( this_star_dp2 );
 }
 
 // remove (d+2)-entities from the (d+2)-manifold entities
 for( std::vector< EntityHandle >::iterator vit = this_star_dp2.begin(); vit != this_star_dp2.end(); ++vit )
 dp2_manifold.erase( *vit );
 
 // remove (d+1)-entities from the (d+1)-entities
 for( std::vector< EntityHandle >::iterator vit = this_star_dp1.begin(); vit != this_star_dp1.end(); ++vit )
 dp1_manifold.erase( *vit );
 
 // (end while)
 }
 
 // check for leftover dp2 manifold entities, these should be in one of the
 // stars
 if( !dp2_manifold.empty() )
 {
 for( Range::iterator rit = dp2_manifold.begin(); rit != dp2_manifold.end(); ++rit )
 {
 }
 }
 
 return MB_SUCCESS;
}
 
//! get (target_dim)-dimensional manifold entities connected to star_entity; that is,
//! the entities with <= 1 connected (target_dim+2)-dimensional adjacent entities;
//! for target_dim=3, just return all of them
//! just insert into the list, w/o clearing manifold list first
ErrorCode MeshTopoUtil::get_manifold( const EntityHandle star_entity, const int target_dim, Range& manifold )
{
 // get all the entities of target dimension connected to star
 Range tmp_range;
 ErrorCode result = mbImpl->get_adjacencies( &star_entity, 1, target_dim, false, tmp_range );
 if( MB_SUCCESS != result ) return result;
 
 // now save the ones which are (target_dim+1)-dimensional manifold;
 // for target_dim=3, just return whole range, since we don't do 4d
 if( target_dim == 3 )
 {
 manifold.merge( tmp_range );
 return MB_SUCCESS;
 }
 
 for( Range::iterator rit = tmp_range.begin(); rit != tmp_range.end(); ++rit )
 {
 Range dum_range;
 // get (target_dim+1)-dimensional entities
 result = mbImpl->get_adjacencies( &( *rit ), 1, target_dim + 1, false, dum_range );
 if( MB_SUCCESS != result ) return result;
 
 // if there are only 1 or zero, add to manifold list
 if( 1 >= dum_range.size() ) manifold.insert( *rit );
 }
 
 return MB_SUCCESS;
}
 
//! get "bridge" or "2nd order" adjacencies, going through dimension bridge_dim
ErrorCode MeshTopoUtil::get_bridge_adjacencies( Range& from_entities,
 int bridge_dim,
 int to_dim,
 Range& to_ents,
 int num_layers )
{
 Range bridge_ents, accum_layers, new_toents( from_entities );
 ErrorCode result;
 if( 0 == num_layers || from_entities.empty() ) return MB_FAILURE;
 
 // for each layer, get bridge-adj entities and accumulate
 for( int nl = 0; nl < num_layers; nl++ )
 {
 Range new_bridges;
 // get bridge ents
 result = mbImpl->get_adjacencies( new_toents, bridge_dim, true, new_bridges, Interface::UNION );
 if( MB_SUCCESS != result ) return result;
 
 // get to_dim adjacencies, merge into to_ents
 Range new_layer;
 if( -1 == to_dim )
 {
 result = mbImpl->get_adjacencies( new_bridges, 3, false, new_layer, Interface::UNION );
 if( MB_SUCCESS != result ) return result;
 for( int d = 2; d >= 1; d-- )
 {
 result = mbImpl->get_adjacencies( to_ents, d, true, new_layer, Interface::UNION );
 if( MB_SUCCESS != result ) return result;
 }
 }
 else
 {
 result = mbImpl->get_adjacencies( new_bridges, to_dim, false, new_layer, Interface::UNION );
 if( MB_SUCCESS != result ) return result;
 }
 
 // subtract last_toents to get new_toents
 accum_layers.merge( new_layer );
 if( nl < num_layers - 1 ) new_toents = subtract( new_layer, new_toents );
 }
 to_ents.merge( accum_layers );
 
 return MB_SUCCESS;
}
 
//! get "bridge" or "2nd order" adjacencies, going through dimension bridge_dim
ErrorCode MeshTopoUtil::get_bridge_adjacencies( const EntityHandle from_entity,
 const int bridge_dim,
 const int to_dim,
 Range& to_adjs )
{
 // get pointer to connectivity for this entity
 const EntityHandle* connect;
 int num_connect;
 ErrorCode result = MB_SUCCESS;
 EntityType from_type = TYPE_FROM_HANDLE( from_entity );
 if( from_type == MBVERTEX )
 {
 connect = &from_entity;
 num_connect = 1;
 }
 else
 {
 result = mbImpl->get_connectivity( from_entity, connect, num_connect );
 if( MB_SUCCESS != result ) return result;
 }
 
 if( from_type >= MBENTITYSET ) return MB_FAILURE;
 
 int from_dim = CN::Dimension( from_type );
 
 Range to_ents;
 
 if( bridge_dim < from_dim )
 {
 // looping over each sub-entity of dimension bridge_dim...
 if( MBPOLYGON == from_type )
 {
 for( int i = 0; i < num_connect; i++ )
 {
 // loop over edges, and get the vertices
 EntityHandle verts_on_edge[2] = { connect[i], connect[( i + 1 ) % num_connect] };
 to_ents.clear();
 ErrorCode tmp_result =
 mbImpl->get_adjacencies( verts_on_edge, 2, to_dim, false, to_ents, Interface::INTERSECT );
 if( MB_SUCCESS != tmp_result ) result = tmp_result;
 to_adjs.merge( to_ents );
 }
 }
 else
 {
 EntityHandle bridge_verts[MAX_SUB_ENTITIES];
 int bridge_indices[MAX_SUB_ENTITIES];
 for( int i = 0; i < CN::NumSubEntities( from_type, bridge_dim ); i++ )
 {
 
 // get the vertices making up this sub-entity
 int num_bridge_verts = CN::VerticesPerEntity( CN::SubEntityType( from_type, bridge_dim, i ) );
 assert( num_bridge_verts >= 0 && num_bridge_verts <= MAX_SUB_ENTITIES );
 CN::SubEntityVertexIndices( from_type, bridge_dim, i, bridge_indices );
 for( int j = 0; j < num_bridge_verts; ++j )
 {
 if( bridge_indices[j] >= 0 && bridge_indices[j] < num_connect )
 bridge_verts[j] = connect[bridge_indices[j]];
 else
 bridge_verts[j] = 0;
 }
 // CN::SubEntityConn(connect, from_type, bridge_dim, i, &bridge_verts[0],
 // num_bridge_verts);
 
 // get the to_dim entities adjacent
 to_ents.clear();
 ErrorCode tmp_result = mbImpl->get_adjacencies( bridge_verts, num_bridge_verts, to_dim, false, to_ents,
 Interface::INTERSECT );
 if( MB_SUCCESS != tmp_result ) result = tmp_result;
 
 to_adjs.merge( to_ents );
 }
 }
 }
 
 // now get the direct ones too, or only in the case where we're
 // going to higher dimension for bridge
 Range bridge_ents, tmp_ents;
 tmp_ents.insert( from_entity );
 ErrorCode tmp_result = mbImpl->get_adjacencies( tmp_ents, bridge_dim, false, bridge_ents, Interface::UNION );
 if( MB_SUCCESS != tmp_result ) return tmp_result;
 
 tmp_result = mbImpl->get_adjacencies( bridge_ents, to_dim, false, to_adjs, Interface::UNION );
 if( MB_SUCCESS != tmp_result ) return tmp_result;
 
 // if to_dimension is same as that of from_entity, make sure from_entity isn't
 // in list
 if( to_dim == from_dim ) to_adjs.erase( from_entity );
 
 return result;
}
 
//! return a common entity of the specified dimension, or 0 if there isn't one
EntityHandle MeshTopoUtil::common_entity( const EntityHandle ent1, const EntityHandle ent2, const int dim )
{
 Range tmp_range, tmp_range2;
 tmp_range.insert( ent1 );
 tmp_range.insert( ent2 );
 ErrorCode result = mbImpl->get_adjacencies( tmp_range, dim, false, tmp_range2 );
 if( MB_SUCCESS != result || tmp_range2.empty() )
 return 0;
 else
 return *tmp_range2.begin();
}
 
//! return the opposite side entity given a parent and bounding entity.
//! This function is only defined for certain types of parent/child types;
//! See CN.hpp::OppositeSide for details.
//!
//! \param parent The parent element
//! \param child The child element
//! \param opposite_element The index of the opposite element
ErrorCode MeshTopoUtil::opposite_entity( const EntityHandle parent,
 const EntityHandle child,
 EntityHandle& opposite_element )
{
 // get the side no.
 int side_no, offset, sense;
 ErrorCode result = mbImpl->side_number( parent, child, side_no, offset, sense );
 if( MB_SUCCESS != result ) return result;
 
 // get the child index from CN
 int opposite_index, opposite_dim;
 int status = CN::OppositeSide( mbImpl->type_from_handle( parent ), side_no, mbImpl->dimension_from_handle( child ),
 opposite_index, opposite_dim );
 if( 0 != status ) return MB_FAILURE;
 
 // now get the side element from MOAB
 result = mbImpl->side_element( parent, opposite_dim, opposite_index, opposite_element );
 if( MB_SUCCESS != result ) return result;
 
 return MB_SUCCESS;
}
 
ErrorCode MeshTopoUtil::split_entities_manifold( Range& entities, Range& new_entities, Range* fill_entities )
{
 Range tmp_range, *tmp_ptr_fill_entity;
 if( NULL != fill_entities )
 tmp_ptr_fill_entity = &tmp_range;
 else
 tmp_ptr_fill_entity = NULL;
 
 for( Range::iterator rit = entities.begin(); rit != entities.end(); ++rit )
 {
 EntityHandle new_entity;
 if( NULL != tmp_ptr_fill_entity ) tmp_ptr_fill_entity->clear();
 
 EntityHandle this_ent = *rit;
 ErrorCode result = split_entities_manifold( &this_ent, 1, &new_entity, tmp_ptr_fill_entity );
 if( MB_SUCCESS != result ) return result;
 
 new_entities.insert( new_entity );
 if( NULL != fill_entities ) fill_entities->merge( *tmp_ptr_fill_entity );
 }
 
 return MB_SUCCESS;
}
 
ErrorCode MeshTopoUtil::split_entities_manifold( EntityHandle* entities,
 const int num_entities,
 EntityHandle* new_entities,
 Range* fill_entities,
 EntityHandle* gowith_ents )
{
 // split entities by duplicating them; splitting manifold means that there is at
 // most two higher-dimension entities bounded by a given entity; after split, the
 // new entity bounds one and the original entity bounds the other
 
#define ITERATE_RANGE( range, it ) for( Range::iterator it = ( range ).begin(); ( it ) != ( range ).end(); ++( it ) )
#define GET_CONNECT_DECL( ent, connect, num_connect ) \
 const EntityHandle* connect = NULL; \
 int num_connect = 0; \
 { \
 ErrorCode connect_result = mbImpl->get_connectivity( ent, connect, num_connect ); \
 if( MB_SUCCESS != connect_result ) return connect_result; \
 }
#define GET_CONNECT( ent, connect, num_connect ) \
 { \
 ErrorCode connect_result = mbImpl->get_connectivity( ent, connect, num_connect ); \
 if( MB_SUCCESS != connect_result ) return connect_result; \
 }
#define TC \
 if( MB_SUCCESS != tmp_result ) \
 { \
 result = tmp_result; \
 continue; \
 }
 
 ErrorCode result = MB_SUCCESS;
 for( int i = 0; i < num_entities; i++ )
 {
 ErrorCode tmp_result;
 
 // get original higher-dimensional bounding entities
 Range up_adjs[4];
 // can only do a split_manifold if there are at most 2 entities of each
 // higher dimension; otherwise it's a split non-manifold
 bool valid_up_adjs = true;
 for( int dim = 1; dim <= 3; dim++ )
 {
 tmp_result = mbImpl->get_adjacencies( entities + i, 1, dim, false, up_adjs[dim] );
 TC;
 if( dim > CN::Dimension( TYPE_FROM_HANDLE( entities[i] ) ) && up_adjs[dim].size() > 2 )
 {
 valid_up_adjs = false;
 break;
 }
 }
 if( !valid_up_adjs ) return MB_FAILURE;
 
 // ok to split; create the new entity, with connectivity of the original
 GET_CONNECT_DECL( entities[i], connect, num_connect );
 EntityHandle new_entity;
 result = mbImpl->create_element( mbImpl->type_from_handle( entities[i] ), connect, num_connect, new_entity );
 TC;
 
 // by definition, new entity and original will be equivalent; need to add explicit
 // adjs to distinguish them; don't need to check if there's already one there,
 // 'cuz add_adjacency does that for us
 for( int dim = 1; dim <= 3; dim++ )
 {
 if( up_adjs[dim].empty() || dim == CN::Dimension( TYPE_FROM_HANDLE( entities[i] ) ) ) continue;
 
 if( dim < CN::Dimension( TYPE_FROM_HANDLE( entities[i] ) ) )
 {
 // adjacencies from other entities to this one; if any of those are equivalent
 // entities, need to make explicit adjacency to new entity too
 for( Range::iterator rit = up_adjs[dim].begin(); rit != up_adjs[dim].end(); ++rit )
 {
 if( equivalent_entities( *rit ) ) result = mbImpl->add_adjacencies( *rit, &new_entity, 1, false );
 }
 }
 else
 {
 
 // get the two up-elements
 EntityHandle up_elem1 = *( up_adjs[dim].begin() ),
 up_elem2 = ( up_adjs[dim].size() > 1 ? *( up_adjs[dim].rbegin() ) : 0 );
 
 // if two, and a gowith entity was input, make sure the new entity goes with
 // that one
 if( gowith_ents && up_elem2 && gowith_ents[i] != up_elem1 && gowith_ents[i] == up_elem2 )
 {
 EntityHandle tmp_elem = up_elem1;
 up_elem1 = up_elem2;
 up_elem2 = tmp_elem;
 }
 
 mbImpl->remove_adjacencies( entities[i], &up_elem1, 1 );
 // (ok if there's an error, that just means there wasn't an explicit adj)
 
 tmp_result = mbImpl->add_adjacencies( new_entity, &up_elem1, 1, false );
 TC;
 if( !up_elem2 ) continue;
 
 // add adj to other up_adj
 tmp_result = mbImpl->add_adjacencies( entities[i], &up_elem2, 1, false );
 TC;
 }
 }
 
 // if we're asked to build a next-higher-dimension object, do so
 EntityHandle fill_entity = 0;
 EntityHandle tmp_ents[2];
 if( NULL != fill_entities )
 {
 // how to do this depends on dimension
 switch( CN::Dimension( TYPE_FROM_HANDLE( entities[i] ) ) )
 {
 case 0:
 tmp_ents[0] = entities[i];
 tmp_ents[1] = new_entity;
 tmp_result = mbImpl->create_element( MBEDGE, tmp_ents, 2, fill_entity );
 TC;
 break;
 case 1:
 tmp_result = mbImpl->create_element( MBPOLYGON, connect, 2, fill_entity );
 TC;
 // need to create explicit adj in this case
 tmp_result = mbImpl->add_adjacencies( entities[i], &fill_entity, 1, false );
 TC;
 tmp_result = mbImpl->add_adjacencies( new_entity, &fill_entity, 1, false );
 TC;
 break;
 case 2:
 tmp_ents[0] = entities[i];
 tmp_ents[1] = new_entity;
 tmp_result = mbImpl->create_element( MBPOLYHEDRON, tmp_ents, 2, fill_entity );
 TC;
 break;
 }
 if( 0 == fill_entity )
 {
 result = MB_FAILURE;
 continue;
 }
 fill_entities->insert( fill_entity );
 }
 
 new_entities[i] = new_entity;
 
 } // end for over input entities
 
 return result;
}
 
ErrorCode MeshTopoUtil::split_entity_nonmanifold( EntityHandle split_ent,
 Range& old_adjs,
 Range& new_adjs,
 EntityHandle& new_entity )
{
 // split an entity into two entities; new entity gets explicit adj to new_adjs,
 // old to old_adjs
 
 // make new entities and add adjacencies
 // create the new entity
 EntityType split_type = mbImpl->type_from_handle( split_ent );
 
 ErrorCode result;
 if( MBVERTEX == split_type )
 {
 double coords[3];
 result = mbImpl->get_coords( &split_ent, 1, coords );RR;
 result = mbImpl->create_vertex( coords, new_entity );RR;
 }
 else
 {
 const EntityHandle* connect;
 int num_connect;
 result = mbImpl->get_connectivity( split_ent, connect, num_connect );RR;
 result = mbImpl->create_element( split_type, connect, num_connect, new_entity );RR;
 
 // remove any explicit adjacencies between new_adjs and split entity
 for( Range::iterator rit = new_adjs.begin(); rit != new_adjs.end(); ++rit )
 mbImpl->remove_adjacencies( split_ent, &( *rit ), 1 );
 }
 
 if( MBVERTEX != split_type )
 {
 // add adj's between new_adjs & new entity, old_adjs & split_entity
 for( Range::iterator rit = new_adjs.begin(); rit != new_adjs.end(); ++rit )
 mbImpl->add_adjacencies( new_entity, &( *rit ), 1, true );
 for( Range::iterator rit = old_adjs.begin(); rit != old_adjs.end(); ++rit )
 mbImpl->add_adjacencies( split_ent, &( *rit ), 1, true );
 }
 else if( split_ent != new_entity )
 {
 // in addition to explicit adjs, need to check if vertex is part of any
 // other entities, and check those entities against ents in old and new adjs
 Range other_adjs;
 for( int i = 1; i < 4; i++ )
 {
 result = mbImpl->get_adjacencies( &split_ent, 1, i, false, other_adjs, Interface::UNION );RR;
 }
 other_adjs = subtract( other_adjs, old_adjs );
 other_adjs = subtract( other_adjs, new_adjs );
 for( Range::iterator rit1 = other_adjs.begin(); rit1 != other_adjs.end(); ++rit1 )
 {
 // find an adjacent lower-dimensional entity in old_ or new_ adjs
 bool found = false;
 for( Range::iterator rit2 = old_adjs.begin(); rit2 != old_adjs.end(); ++rit2 )
 {
 if( mbImpl->dimension_from_handle( *rit1 ) != mbImpl->dimension_from_handle( *rit2 ) &&
 common_entity( *rit1, *rit2, mbImpl->dimension_from_handle( *rit1 ) ) )
 {
 found = true;
 old_adjs.insert( *rit1 );
 break;
 }
 }
 if( found ) continue;
 for( Range::iterator rit2 = new_adjs.begin(); rit2 != new_adjs.end(); ++rit2 )
 {
 if( mbImpl->dimension_from_handle( *rit1 ) != mbImpl->dimension_from_handle( *rit2 ) &&
 common_entity( *rit1, *rit2, mbImpl->dimension_from_handle( *rit1 ) ) )
 {
 found = true;
 new_adjs.insert( *rit1 );
 break;
 }
 }
 if( !found ) return MB_FAILURE;
 }
 
 // instead of adjs replace in connectivity
 std::vector< EntityHandle > connect;
 for( Range::iterator rit = new_adjs.begin(); rit != new_adjs.end(); ++rit )
 {
 connect.clear();
 result = mbImpl->get_connectivity( &( *rit ), 1, connect );RR;
 std::replace( connect.begin(), connect.end(), split_ent, new_entity );
 result = mbImpl->set_connectivity( *rit, &connect[0], connect.size() );RR;
 }
 }
 
 return result;
 
 /*
 
 Commented out for now, because I decided to do a different implementation
 for the sake of brevity. However, I still think this function is the right
 way to do it, if I ever get the time. Sigh.
 
 // split entity d, producing entity nd; generates various new entities,
 // see algorithm description in notes from 2/25/05
 const EntityHandle split_types = {MBEDGE, MBPOLYGON, MBPOLYHEDRON};
 ErrorCode result = MB_SUCCESS;
 const int dim = CN::Dimension(TYPE_FROM_HANDLE(d));
 MeshTopoUtil mtu(this);
 
 // get all (d+2)-, (d+1)-cells connected to d
 Range dp2s, dp1s, dp1s_manif, dp2s_manif;
 result = get_adjacencies(&d, 1, dim+2, false, dp2s); RR;
 result = get_adjacencies(&d, 1, dim+1, false, dp1s); RR;
 
 // also get (d+1)-cells connected to d which are manifold
 get_manifold_dp1s(d, dp1s_manif);
 get_manifold_dp2s(d, dp2s_manif);
 
 // make new cell nd, then ndp1
 result = copy_entity(d, nd); RR;
 EntityHandle tmp_connect[] = {d, nd};
 EntityHandle ndp1;
 result = create_element(split_types[dim],
 tmp_connect, 2, ndp1); RR;
 
 // modify (d+2)-cells, depending on what type they are
 ITERATE_RANGE(dp2s, dp2) {
 // first, get number of connected manifold (d+1)-entities
 Range tmp_range, tmp_range2(dp1s_manif);
 tmp_range.insert(*dp2);
 tmp_range.insert(d);
 tmp_result = get_adjacencies(tmp_range, 1, false, tmp_range2); TC;
 EntityHandle ndp2;
 
 // a. manif (d+1)-cells is zero
 if (tmp_range2.empty()) {
 // construct new (d+1)-cell
 EntityHandle ndp1a;
 EntityHandle tmp_result = create_element(split_types[dim],
 tmp_connect, 2, ndp1a); TC;
 // now make new (d+2)-cell
 EntityHandle tmp_connect2[] = {ndp1, ndp1a};
 tmp_result = create_element(split_types[dim+1],
 tmp_connect2, 2, ndp2); TC;
 // need to add explicit adjacencies, since by definition ndp1, ndp1a will be equivalent
 tmp_result = add_adjacencies(ndp1a, &dp2, 1, false); TC;
 tmp_result = add_adjacencies(ndp1a, &ndp2, 1, false); TC;
 tmp_result = add_adjacencies(ndp1, &ndp2, 1, false); TC;
 
 // now insert nd into connectivity of dp2, right after d if dim < 1
 std::vector<EntityHandle> connect;
 tmp_result = get_connectivity(&dp2, 1, connect); TC;
 if (dim < 1) {
 std::vector<EntityHandle>::iterator vit = std::find(connect.begin(), connect.end(), d);
 if (vit == connect.end()) {
 result = MB_FAILURE;
 continue;
 }
 connect.insert(vit, nd);
 }
 else
 connect.push_back(nd);
 tmp_result = set_connectivity(dp2, connect); TC;
 
 // if dim < 1, need to add explicit adj from ndp2 to higher-dim ents, since it'll
 // be equiv to other dp2 entities
 if (dim < 1) {
 Range tmp_dp3s;
 tmp_result = get_adjacencies(&dp2, 1, dim+3, false, tmp_dp3s); TC;
 tmp_result = add_adjacencies(ndp2, tmp_dp3s, false); TC;
 }
 } // end if (tmp_range2.empty())
 
 // b. single manifold (d+1)-cell, which isn't adjacent to manifold (d+2)-cell
 else if (tmp_range2.size() == 1) {
 // b1. check validity, and skip if not valid
 
 // only change if not dp1-adjacent to manifold dp2cell; check that...
 Range tmp_adjs(dp2s_manif);
 tmp_result = get_adjacencies(&(*tmp_range2.begin()), 1, dim+2, false, tmp_adjs); TC;
 if (!tmp_adjs.empty()) continue;
 
 EntityHandle dp1 = *tmp_range2.begin();
 
 // b2. make new (d+1)- and (d+2)-cell next to dp2
 
 // get the (d+2)-cell on the other side of dp1
 tmp_result = get_adjacencies(&dp1, 1, dim+2, false, tmp_adjs); TC;
 EntityHandle odp2 = *tmp_adjs.begin();
 if (odp2 == dp2) odp2 = *tmp_adjs.rbegin();
 
 // get od, the d-cell on dp1_manif which isn't d
 tmp_result = get_adjacencies(&dp1_manif, 1, dim, false, tmp_adjs); TC;
 tmp_adjs.erase(d);
 if (tmp_adjs.size() != 1) {
 result = MB_FAILURE;
 continue;
 }
 EntityHandle od = *tmp_adjs.begin();
 
 // make a new (d+1)-cell from od and nd
 tmp_adjs.insert(nd);
 tmp_result = create_element(split_types[1], tmp_adjs, ndp1a); TC;
 
 // construct new (d+2)-cell from dp1, ndp1, ndp1a
 tmp_adjs.clear();
 tmp_adjs.insert(dp1); tmp_adjs.insert(ndp1); tmp_adjs.insert(ndp1a);
 tmp_result = create_element(split_types[2], tmp_adjs, ndp2); TC;
 
 // b3. replace d, dp1 in connect/adjs of odp2
 std::vector<EntityHandle> connect;
 tmp_result = get_connectivity(&odp2, 1, connect); TC;
 if (dim == 0) {
 *(std::find(connect.begin(), connect.end(), d)) = nd;
 remove_adjacency(dp1, odp2);
 
 
 
 // if dp1 was explicitly adj to odp2, remove it
 remove_adjacency
 
 ...
 
 */
}
 
//! return whether entity is equivalent to any other of same type and same vertices;
//! if equivalent entity is found, it's returned in equiv_ents and return value is true,
//! false otherwise.
bool MeshTopoUtil::equivalent_entities( const EntityHandle entity, Range* equiv_ents )
{
 const EntityHandle* connect = NULL;
 int num_connect = 0;
 ErrorCode result = mbImpl->get_connectivity( entity, connect, num_connect );
 if( MB_SUCCESS != result ) return false;
 
 Range dum;
 result = mbImpl->get_adjacencies( connect, num_connect, mbImpl->dimension_from_handle( entity ), false, dum );
 dum.erase( entity );
 
 if( NULL != equiv_ents )
 {
 equiv_ents->swap( dum );
 }
 
 if( !dum.empty() )
 return true;
 else
 return false;
}
 
} // namespace moab